AM5728的McASP7的发送I2S音频数据时,McASP7作为master,时钟AHCLKX的MCLK=12.288MHz是由外面输入到AM5728。
然后McASP7的LRCLK可否设定输出来192KHz?
如何设置寄存器,使McASP7的SCLK输出来12.288MHz?
Sheldon Wang:
The same question as Lei huang2.
How to setting: Multichannel Audio Serial Port 7 as Audio I2S output master mode?
1, So far mcasp7 [mcasp7_ahclkx] setting asI2S MCLK = 20MHz, but can not setting as 12.288MHz or 24,576MHz.
It is AM5728 chip internal colock bus limitation, right?
If it can not do this, we can add a Crystal on board.
2, If MCLK can not generate base on I2S standard format, how can setting [mcasp7_aclkx] and [mcasp7_fsx] as BCK and LRCLK as below clock.
They need meet as I2S standard as [mcasp7_aclkx] as BCK = 12.288MHz/64Fs or 6.144MHz/128Fs or 3.072MHz/256Fs.
And [mcasp7_fsx] as LRCLK = 192KHz or 96KHz or 48KHz.
Those are standard I2S format for audio master output.
We will driver standalone DAC, chip AD1955.
lei huang2:
回复 Sheldon Wang:
May you confirm this critical information:
1, So far mcasp7 [mcasp7_ahclkx] setting asI2S MCLK = 20MHz, but can not setting as 12.288MHz or 24,576MHz.
lei huang2:
回复 Sheldon Wang:
1 mcasp7 [mcasp7_ahclkx] can not setting as 12.288MHz or 24,576MHz, am I right? where or which document can I find the information about this restriction?